Zoom Realtime Media Streams (RTMS) SDK

Bindings for real-time audio, video, and transcript streams from Zoom Meetings

Supported Products

The RTMS SDK works with multiple Zoom products:

• Zoom Meetings - Real-time streams from Zoom Meetings
• Zoom Webinars - Broadcast-quality streams from Zoom Webinars
• Zoom Video SDK - Custom video experiences with RTMS access
• Zoom Contact Center - Real-time streams from Zoom Contact Center voice engagements

See examples/ for complete guides and code samples.

Platform Support Status

We are actively working to expand both language and platform support in future releases.

Overview

The RTMS SDK allows developers to:

• Connect to live Zoom meetings
• Process real-time media streams (audio, video, transcripts)
• Receive events about session and participant updates
• Build applications that interact with Zoom meetings in real-time
• Handle webhook events with full control over validation and responses

Installation

Node.js

⚠️ Requirements: Node.js >= 22.0.0 (Node.js 24 LTS recommended)

The RTMS SDK uses N-API versions 9 and 10, which require Node.js 22.0.0 or higher.

# Check your Node.js version
node --version

# Install the package
npm install @zoom/rtms

Using NVM

If you're using an older version of Node.js:

# Using nvm (recommended)
nvm install 24       # Install Node.js 24 LTS (recommended)
nvm use 24

# Or install Node.js 22 LTS (minimum supported)
nvm install 22
nvm use 22

# Reinstall the package
npm install @zoom/rtms

Python

⚠️ Requirements: Python >= 3.10 (Python 3.10, 3.11, 3.12, or 3.13)

The RTMS SDK requires Python 3.10 or higher.

# Check your Python version
python3 --version

# Install from PyPI
pip install rtms

If you're using an older version of Python:

# Using pyenv (recommended)
pyenv install 3.12
pyenv local 3.12

# Or using your system's package manager
# Ubuntu/Debian: sudo apt install python3.12
# macOS: brew install python@3.12

Usage

Regardless of the language that you use the RTMS SDK follows the same basic steps:

• Receive and validate the webhook event
• Create an RTMS SDK Client
• Assign data callbacks to that client
• Join the meeting with the event payload

Configure

All SDK languages read from the environment or a .env file:

# Required - Your Zoom OAuth credentials
ZM_RTMS_CLIENT=your_client_id
ZM_RTMS_SECRET=your_client_secret

# Optional - Webhook server configuration
ZM_RTMS_PORT=8080
ZM_RTMS_PATH=/webhook

# Optional - Logging configuration
ZM_RTMS_LOG_LEVEL=debug          # error, warn, info, debug, trace
ZM_RTMS_LOG_FORMAT=progressive    # progressive or json
ZM_RTMS_LOG_ENABLED=true          # true or false

Node.js

For more details, see our Quickstart App

import rtms from "@zoom/rtms";

// CommonJS
// const rtms = require('@zoom/rtms').default;

rtms.onWebhookEvent(({event, payload}) => {
    if (event !== "meeting.rtms_started") return;

    const client = new rtms.Client();
    
    client.onAudioData((data, timestamp, metadata) => {
        console.log(`Received audio: ${data.length} bytes from ${metadata.userName}`);
    });

    client.join(payload);
});

Production note: The example above does not validate the incoming webhook signature. Zoom cryptographically signs every webhook — production apps must verify signatures before processing. See Webhook Validation

Python

For more details, see our Quickstart App

Environment Setup

Create a virtual environment and install dependencies:

# Create virtual environment
python3 -m venv .venv

# Activate virtual environment
source .venv/bin/activate  # On Windows: .venv\Scripts\activate

# Install dependencies
pip install python-dotenv

# Install RTMS SDK
pip install rtms

Quickstart

import rtms
from dotenv import load_dotenv

load_dotenv()

clients = {}


@rtms.on_webhook_event
def handle_webhook(webhook):
    event = webhook.get('event')
    payload = webhook.get('payload', {})
    stream_id = payload.get('rtms_stream_id')

    if event == 'meeting.rtms_stopped':
        client = clients.pop(stream_id, None)
        if client:
            client.leave()
        return

    if event != 'meeting.rtms_started':
        return

    client = rtms.Client()
    clients[stream_id] = client

    @client.on_transcript_data
    def _(data, _, timestamp, metadata):
        print(f'[transcript] ts={timestamp} user="{metadata.userName}": {data.decode()}')

    client.join(payload)


rtms.run()

Production note: The example above does not validate the incoming webhook signature. Zoom cryptographically signs every webhook — production apps must verify signatures before processing. See Webhook Validation

Troubleshooting

If you encounter issues some of these steps may help.

1. Segmentation Fault / Crash on Startup

Symptoms:

• Immediate crash when requiring/importing the module
• Error message: Segmentation fault (core dumped)
• Stack trace shows napi_module_register_by_symbol

Root Cause: Using Node.js version < 22.0.0

Solution: See Using NVM

Prevention:

• Always use Node.js 22.0.0 or higher
• Use recommended version with .nvmrc: nvm use (Node.js 24 LTS)
• Check version before installing: node --version

2. Platform Support

Verify you're using a supported platform (darwin-arm64 or linux-x64)

3. SDK Files

Ensure RTMS C++ SDK files are correctly placed in the appropriate lib directory

4. Build Mode

Try both debug and release modes (npm run debug or npm run release)

5. Dependencies

Verify all prerequisites are installed

6. Audio Defaults Mismatch

This SDK uses different default audio parameters than the raw RTMS WebSocket protocol for better out-of-the-box quality. If you need to match the WebSocket protocol defaults, see #92 for details.

7. Identifying Speakers with Mixed Audio Streams

When using AUDIO_MIXED_STREAM, the audio callback's metadata does not identify the current speaker since all participants are mixed into a single stream. To identify who is speaking, use the onActiveSpeakerEvent callback:

Node.js:

client.onActiveSpeakerEvent((timestamp, userId, userName) => {
    console.log(`Active speaker: ${userName} (${userId})`);
});

Python:

@client.onActiveSpeakerEvent
def on_active_speaker(timestamp, user_id, user_name):
    print(f"Active speaker: {user_name} ({user_id})")

This callback notifies your application whenever the active speaker changes in the meeting. You can also use the lower-level onEventEx function with the active speaker event type directly. See #80 for more details.

Building from Source

The RTMS SDK can be built from source using either Docker (recommended) or local build tools.

Using Docker (Recommended)

Prerequisites

• Docker and Docker Compose
• Zoom RTMS C++ SDK files (contact Zoom for access)
• Task installed (or use Docker's Task installation)

Steps

# Clone the repository
git clone https://github.com/zoom/rtms.git
cd rtms

# Place your SDK library files in the lib/{arch} folder
# For linux-x64:
cp ../librtmsdk.0.2025xxxx/librtmsdk.so.0 lib/linux-x64

# For darwin-arm64 (Apple Silicon):
cp ../librtmsdk.0.2025xxxx/librtmsdk.dylib lib/darwin-arm64

# Place the include files in the proper directory
cp ../librtmsdk.0.2025xxxx/h/* lib/include

# Build using Docker Compose with Task
docker compose run --rm build task build:js    # Build Node.js for linux-x64
docker compose run --rm build task build:py    # Build Python wheel for linux-x64

# Or use convenience services
docker compose run --rm test-js                # Build and test Node.js
docker compose run --rm test-py                # Build and test Python

Docker Compose creates distributable packages for linux-x64 (prebuilds for Node.js, wheels for Python). Use this when developing on macOS to build Linux packages for distribution.

Building Locally

Prerequisites

• Node.js (>= 22.0.0, LTS recommended)
• Python 3.10+ with pip (for Python build)
• CMake 3.25+
• C/C++ build tools
• Task (go-task) - https://taskfile.dev/installation/
• Zoom RTMS C++ SDK files (contact Zoom for access)

Steps

# Install system dependencies
## macOS
brew install cmake go-task python@3.13 node@24

## Linux
sudo apt update
sudo apt install -y cmake python3-full python3-pip npm
sh -c "$(curl --location https://taskfile.dev/install.sh)" -- -d -b ~/.local/bin

# Clone and set up the repository
git clone https://github.com/zoom/rtms.git
cd rtms

# Place SDK files in the appropriate lib directory
# lib/linux-x64/ or lib/darwin-arm64/

# Verify your environment meets requirements
task doctor

# Setup project (fetches SDK if not present, installs dependencies)
task setup

# Build for specific language and platform
task build:js             # Build Node.js for current platform
task build:js:linux       # Build Node.js for Linux (via Docker)
task build:js:darwin      # Build Node.js for macOS

task build:py             # Build Python for current platform
task build:py:linux       # Build Python wheel for Linux (via Docker)
task build:py:darwin      # Build Python wheel for macOS

Development Commands

The project uses Task (go-task) for build orchestration. Commands follow the pattern: task <action>:<lang>:<platform>

# See all available commands
task --list

# Verify environment
task doctor                   # Check Node, Python, CMake, Docker versions

# Setup project
task setup                    # Fetch SDK and install dependencies

# Build modes
BUILD_TYPE=Debug task build:js    # Build in debug mode
BUILD_TYPE=Release task build:js  # Build in release mode (default)

# Debug logging for C++ SDK callbacks
RTMS_DEBUG=ON task build:js       # Enable verbose callback logging

For Contributors

For detailed contribution guidelines, build instructions, and troubleshooting, see CONTRIBUTING.md.

For Maintainers

If you're a maintainer looking to build, test, or publish new releases of the RTMS SDK, please refer to PUBLISHING.md

License

This project is licensed under the MIT License - see the LICENSE.md file for details.